21011221011100 has 18 divisors (see below), whose sum is σ = 45594349594304. Its totient is φ = 8404488404400.

The previous prime is 21011221011097. The next prime is 21011221011101. The reversal of 21011221011100 is 111012211012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011221011101) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105056104956 + ... + 105056105155.

Almost surely, 2^{21011221011100} is an apocalyptic number.

21011221011100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011221011100 is an abundant number, since it is smaller than the sum of its proper divisors (24583128583204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21011221011100 is a wasteful number, since it uses less digits than its factorization.

21011221011100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210112210125 (or 210112210118 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21011221011100 its reverse (111012211012), we get a palindrome (21122233222112).

The spelling of 21011221011100 in words is "twenty-one trillion, eleven billion, two hundred twenty-one million, eleven thousand, one hundred".